Gurobi 5.0.1 (linux64) logging started Wed Apr 24 01:33:15 2013

Optimize a model with 36660 rows, 36060 columns and 144060 nonzeros
Presolve removed 2017 rows and 0 columns
Presolve time: 0.22s
Presolved: 34643 rows, 36060 columns, 140026 nonzeros
Variable types: 36000 continuous, 60 integer (60 binary)

Root relaxation: objective 5.543671e+04, 4538 iterations, 0.61 seconds

    Nodes    |    Current Node    |     Objective Bounds      |     Work
 Expl Unexpl |  Obj  Depth IntInf | Incumbent    BestBd   Gap | It/Node Time

     0     0 55436.7138    0    4          - 55436.7138     -      -    0s
H    0     0                    56128.000000 55436.7138  1.23%     -    1s
H    0     0                    55655.000000 55436.7138  0.39%     -    1s
     0     0 55436.7997    0    5 55655.0000 55436.7997  0.39%     -    1s
     0     0 55436.7997    0    5 55655.0000 55436.7997  0.39%     -    1s
H    0     0                    55483.000000 55436.7997  0.08%     -    1s
     0     0 55436.7997    0    4 55483.0000 55436.7997  0.08%     -    2s
     0     0 55436.7997    0    5 55483.0000 55436.7997  0.08%     -    2s
     0     0 55436.7997    0    5 55483.0000 55436.7997  0.08%     -    2s
     0     2 55439.2949    0    5 55483.0000 55439.2949  0.08%     -    3s

Cutting planes:
  Gomory: 1
  Flow cover: 1

Explored 2 nodes (6349 simplex iterations) in 3.29 seconds
Thread count was 1 (of 16 available processors)

Optimal solution found (tolerance 1.00e-04)
Best objective 5.548300000000e+04, best bound 5.547905263158e+04, gap 0.0071%